Embodiments of the present invention relate to a nonvolatile memory device and a method of operating the same and, more particularly, to a nonvolatile memory device capable of reducing the operating time and a method of operating the same.
A nonvolatile memory device enables data to be electrically programmed and erased and does not use a refresh function of rewriting the data in a specific cycle.
In general, the nonvolatile memory device is programmed through an incremental step pulse program (ISPP) method.
The ISPP method is described below.
After supplying a program pulse to the memory cells of the nonvolatile memory device, a program verification operation is performed in order to check whether the threshold voltages of the memory cells have been programmed higher than a target threshold voltage or not. If, as a result of the program verification operation, the threshold voltage of any of the memory cells is lower than the target threshold voltage, the program pulse raised by a step voltage is supplied to the memory cells and the program verification operation is performed again. That is, the above operation is repeatedly performed until the memory cells reach the target threshold voltage or higher.
In general, after an operation of supplying one program pulse and a program verification operation are completed, a control logic within a microcontroller for controlling the program operation performs an operation of newly setting up pieces of option information, such as a voltage of a new program pulse, the number of times that the program pulse is supplied, and a pass voltage supplied to an unselected word line. After the setup operation is completed, the control logic performs a page buffer check operation of determining whether a page buffer is normal or not.
In this case, the total time that the nonvolatile memory device performs the program operation may increase because the control logic separately performs the setup operation and the page buffer check operation.